Old English gylt "crime, sin, fault, fine," of unknown origin, though some suspect a connection to Old English gieldan "to pay for, debt," but OED editors find this "inadmissible phonologically." The mistaken use for "sense of guilt" is first recorded 1680s. Guilt by association recorded by 1919.

v.

"to influence someone by appealing to his sense of guiltiness," by 1995, from guilt (n.). Related: Guilted; guilting. Old English also had a verbal form, gyltan "to commit an offense."